Electronic circuit design often requires the use of various interface circuitries such as liquid crystal displays (LCDs) and capacitive sensor arrays that enable the user to interact with or receive information from an electronic circuit. Typically, LCD displays are driven by dedicated LCD driver controllers which enable a circuit to control an LCD display to display desired information on the segments of the LCD display. Similarly, dedicated sensing circuitry may be used to detect the activation of various capacitive switches within a capacitive sensor array enabling a user to input particular information into a circuit.
An additional requirement of many capacitive switch sensing circuitries is the ability to connect to each of the capacitive switches within an array and this, of course, requires a large number of I/O pins to be associated with the capacitive sensing circuitries. The requirements of a large number of I/O pins dedicated to each capacitive switch, dedicated capacitive sensing circuitry and LCD driver controller circuitry can result in an increase in chip size in order to include all of these components. Therefore, there is a need for circuit designers to have the ability to more conveniently implement capacitive sensor arrays and LCD drivers within circuit designs that do not require the complexities and space limitations associated with existing dedicated circuitries.
With any electronic device such as an LCD controller, it is often desirable to be able to maintain certain functionalities of the controller in a powered state under certain circumstances while limiting other functionalities in order to conserve power. One example of this with respect to an LCD controller is when the LCD controller is generating a particular continuous display that does not change for long periods of time. In this case, it would be desirable to maintain the continuously occurring display while minimizing the power consumption by the components within the controller.